Adversarial Training with Fast Gradient Projection Method against Synonym Substitution based Text Attacks

Adversarial training is the most empirically successful approach in improving the robustness of deep neural networks for image classification.For text classification, however, existing synonym substitution based adversarial attacks are effective but not efficient to be incorporated into practical text adversarial training. Gradient-based attacks, which are very efficient for images, are hard to be implemented for synonym substitution based text attacks due to the lexical, grammatical and semantic constraints and the discrete text input space. Thereby, we propose a fast text adversarial attack method called Fast Gradient Projection Method (FGPM) based on synonym substitution, which is about 20 times faster than existing text attack methods and could achieve similar attack performance. We then incorporate FGPM with adversarial training and propose a text defense method called Adversarial Training with FGPM enhanced by Logit pairing (ATFL). Experiments show that ATFL could significantly improve the model robustness and block the transferability of adversarial examples.Comment: Accepted by AAAI 2021, code is available at https://github.com/JHL-HUST/FGP

Study on Oil Pressure Characteristics and Trajectory Tracking Control in Shift Process of Wet-Clutch for Electric Vehicles

Accurate control of oil pressure of wet-clutch is of great importance for improving shift quality. Based on dynamic models of two-gear planetary transmission and hydraulic control system, a trajectory tracking model of oil pressure was built by sliding mode control method. An experiment was designed to verify the validity of hydraulic control system, through which the relationship between duty cycle of on-off valve and oil pressure of clutch was determined. The tracking effect was analyzed by simulation. Results showed that oil pressure could follow well the optimal trajectory and the shift quality was effectively improved

The Effects of Storage Conditions on Lycopene Content and Color of Tomato Hot Pot Sauce

Tomato hot pot sauce (THPS) at different storage temperatures (0, 25, and 37°C) and with two kinds of packaging for 120 days was investigated in this study. High performance liquid chromatography was employed for detecting lycopene and 5-hydroxymethylfurfural (HMF). The changes of lycopene and HMF during storage were regressed with kinetic equation of both zero-order and first-order models, and the latter fitted better. The kinetic equation constant (k value) of lycopene or HMF at 37°C was higher than that at 25°C. The k value of lycopene of PET/PE (P1) packaged THPS was 1.60 times of that of PET/Al/EAA/PE (P2) packaged at 37°C, while it was 2.12 times at 25°C. The k value of HMF of P1 packaged THPS was 1.69 times of that of P2 packaged at 37°C, while it was 1.01 times at 25°C. Significant correlations between color index of L⁎, a⁎, and a⁎/b⁎ and lycopene or HMF were found at storage temperature. Browning color was attributed to both Maillard reaction and degradation of lycopene. In conclusion, lower storage temperature and stronger oxygen barrier property of package could maintain color stability and extend shelf life

Non-Standard Errors

In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants

AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

A Video Specific Instruction Set Architecture for ASIP design

This paper describes a novel video specific instruction set architecture for ASIP design. With single instruction multiple data (SIMD) instructions, two destination modes, and video specific instructions, an instruction set architecture is introduced to enhance the performance for video applications. Furthermore, we quantify the improvement on H.263 encoding. In this paper, we evaluate and compare the performance of VS-ISA, other DSPs (digital signal processors), and conventional SIMD media extensions in the context of video coding. Our evaluation results show that VS-ISA improves the processor's performance by approximately 5x on H.263 encoding, and VS-ISA outperforms other architectures by 1.6x to 8.57x in computing IDCT

A Retargetable Compiler of VLIW ASIP for Media Signal Processing

Abstract * In the last decade extensive researches have been carried out in ASIP (Application Specific Instruction Processor) design field. One of the key steps in ASIP design is code generation by a retargetable compiler. In this paper we describe our experience in implementing a retargetable compiler for VLIW ASIP based on ORC (Open Research Compiler) framework. Orienting towards a new register file access architecture model, we narrate the process making modifications on ORC framework to get the compiler. The experimental results indicate that our method is effective to get compilers retargeting at VLIW ASIPs

Complex Deformation of Central and North China Through Pn Velocity and Anisotropy Tomography

Abstract Using our recently developed Pn tomography method, we obtain high‐resolution Pn velocity and anisotropy structures of uppermost mantle beneath the Central and North China, which provide useful insight concerning the mechanism of intraplate mantle dynamics. The consistency between the new Pn model and seismic reflection/refraction profiles demonstrates the high quality of our model. Based on the Pn anisotropy structure surrounding the Alxa Block, we infer that material extrusion from northeastern Tibet was impeded and turned to the west and south edges of the Alxa Block. The Pn structures beneath the Sichuan Basin and Songpan‐Ganzi Orogen suggest that the stable Sichuan Basin impeded material extrusion from the Tibetan Plateau and caused material from Tibet to be extruded separately along the west and northwest edges of the Sichuan Basin. To the north of the Sichuan Basin, we infer that the extrusion has ceased within the Songpan‐Ganzi Orogen rather than to further east. The high Pn velocities beneath the Qinling Orogen do not support the proposal of large‐scale eastward material escaping flow in the shallow mantle beneath the western Qinling Orogen. The Pn velocity distribution beneath the North China Craton indicates that hot material from the mantle is more likely to upwell beneath deep faults or active orogenic areas. Our model indicates that the northern and central parts of the Ordos Block retain stable structures at the uppermost mantle, while its southeastern has been reworked by hot material